This invention relates to a process for preparing pillared interlayered clays. In another aspect, this invention relates to pillared interlayered clays having improved cracking activity. In a further aspect, this invention relates to cracking catalysts comprising pillared interlayered clays having improved cracking activity. In yet another aspect, this invention relates to a process for cracking hydrocarbon-containing feed streams employing catalysts comprising pillared interlayered clays having improved cracking activity.
The preparation of pillared interlayered clay compositions by reacting a smectite-type clay with an aqueous solutions of suitable polymeric cationic hydroxy metal complexes of metals, such as aluminum, titanium, zirconium and chromium, is well known. Upon dehydration of the reaction product, there results a smectite clay which includes additional metal oxide, such as oxide of Al, Ti, Zr or Cr, in the form of pillars interspersed between the clay layers, as is illustrated in U.S. Pat. Nos. 4,238,364, 4,216,188 and 4,176,090, herein incorporated by reference. Even though these known clay products having interspersed pillars of metal oxide, such as oxide of Al, Ti, Zr or Cr, (said products being referred to hereinafter as pillared interlayered clays) exhibit various advantages over untreated smectite clays and can be used as cracking catalysts or components thereof, there is an ever present need to develop new pillared interlayered clays possessing further improved surface properties, steam stability and cracking activity.